You are not logged in.
Since a full system upgrade earlier today I have screen flickering in KDE.
This is a Macbook Pro 11,4 Retina with an i7 4870HQ and hybrid radeon graphics (which I've never needed/used) so it's just using intel graphics.
It's not a hardware issue as I also have OSX installed and it doesn't happen there. dmesg shows several broadcom issues, but installing either b43-firmware, broadcom-wl-dmks or broadcom-wl-dmks stops wifi working. lspci | grep Network shows it's a BCM43602 (rev 01).
The following threads offer suggestions:
https://bbs.archlinux.org/viewtopic.php?id=196888
https://ubuntuforums.org/showthread.php?t=2266696
The latter suggests it's a broadcom driver issue but installing the driver breaks wifi and does not fix the screen flicker issue. I have xf86-video-intel installed. And installed xf86-video-ati just in case it's a problem with the hybrid graphics.
I'm not sure why this started today, I'd be very grateful for any suggestions!
edit: The flicker stops if I change the resolution to 1920x1080 instead of the native 2880x1800
Last edited by Tom B (2016-11-16 12:30:55)
Offline
Mod note: not a pacman/upgrade issue, moving to kernel/hardware.
Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD
Making lemonade from lemons since 2015.
Offline
Update: The two suggestions in the wiki ( https://wiki.archlinux.org/index.php/In … flickering )
Rc6 sleep modes (see intel#RC6_sleep_modes_(enable_rc6)), can be disabled with i915.enable_rc6=0.
Panel Self Refresh (PSR) FS#49628 FS#49371 FS#50605, enabled by default since kernel mainline 4.6. To disable this feature use the option i915.enable_psr=0.
Appear to have no effect
edit: I wanted to try differet DRI settings as suggested by the wiki but if I create 20-intel.conf with any contents, X will not start and says "No screens found". The `20-intel.conf` I'm using is a simplified one:
```
Section "Device"
Identifier "Intel Graphics"
Driver "intel"
# Option "DRI" "2"
EndSection
```
With this file, X fails to start at all.
edit 2: It appears that intel graphics are not being recognised at all and everything is being handled by the AMD GPU. I wouldn't really care but it appears to be the cause of the flicker. xrandr --listproviders shows only the AMD GPU and not the Intel Graphics I was expecting.
edit 3: I tried the LTS kernel, the flicker is still there so more likely a driver issue then a kernel issue. I booted into an 6 month old Mint Live USB which doesn't have the flicker problem and works as expected, and xrandr also shows a single provider so presumably that's using the amd gpu as well.
Last edited by Tom B (2016-11-16 19:52:41)
Offline
The plot thickens: This is temperamental. Roughly 1 in 5 times the mac boots or wakes up from suspend the issue happens. Once it starts, it's difficult to stop it and takes several suspend/wake cycles or boots to get back into a normal state.
However, connecting an external display via HDMI (i didn't test displayport) fixes it 100% of the time, it must issue some kind of xorg reset. I'd be happy if I could feign this HDMI disconnect and mimic whatever connecting the monitor does, even if I have to run a command every time the flicker happens I'd be happy with that workaround. I thought `xrandr -q` might do it but unfortunately not. Are there any xrandr commands I can run to force a complete redraw of the screens?
Offline
This also hit me as well. Same behavior. I noticed that it's less of a deal when I use LXDE over Gnome 3.
Offline